This May 13, 2014 file photo shows a row of Google self-driving Lexus cars at a Google event outside the Computer History Museum in Mountain View, Calif. AP Tesla and Google may both be developing self-driving cars, but the technology behind their driverless cars is more different than you might think.

Sure both companies use a number of similar sensors, mapping technology, and software systems that enable the cars to learn from each other, but there's one big difference between the two companies' driverless cars: the sensing technology that acts as the eyes of the vehicle.

Like humans, self-driving cars must be able to see their environment so that they can make decisions about how to safely navigate on the road. Companies developing self-driving technology, though, don't always see eye to eye (see what I did there?) when it comes to what kind of sensors should be used to give a car sight.

Google's self-driving cars uses LIDAR (light-sensing radar), which is a remote sensing technology that uses lasers to map out the world around it. The light reflected from the laser beaming on objects is measure to determine the distance between the car and its environment.

Google

LIDAR is considered by some to be the best technology to use in self-driving cars because it is highly accurate and enables the car to be able to localize its positioning almost perfectly on an existing map.

But, LIDAR is not cheap. In fact, it can cost as much as $80,000 for just one advanced sensor.

What's more, though, Tesla CEO Elon Musk said the technology is overkill and not really necessary to make cars fully autonomous.

"I don't think you need LIDAR. I think you can do this all with passive optical and then with maybe one forward RADAR," Musk said during at a press conference in October. "I think that completely solves it without the use of LIDAR. I'm not a big fan of LIDAR, I don't think it makes sense in this context."

A LIDAR sensor on top of a Google self-driving car. Google/Screenshot

So, at least for now, Tesla, like many other car companies developing self-driving technology, has opted to use high-tech camera sensors as the primary eyes of the car.

However, it's cars are also equipped with 12 long-range ultrasonic sensors that provide 360 degree vision, and a forward facing RADAR system to help enable its semi-autonomous Autopilot system.

A visualization of Tesla's Autopilot system. Vimeo/Tesla

The forward looking camera, created by Mobileye, is mounted on the front of the rearview mirror and features advanced software that allows it to not only measure distance, but also read signs, and detect pedestrians.

Tesla vehicles built since October of last year are all equipped with the necessary hardware that powers Autopilot.

However, it's worth noting, that Tesla will likely add additional sensing technology to future vehicles to enable full autonomy. It's possible it could even implement LIDAR in its cars eventually once the price comes down.